22-week male fetus with L5 defect

Three-dimensional (3D) ultrasound acquisition with multiplanar reconstruction in the transverse plane and 3D surface rendering in the coronal plane at L4 (A) and L5 (B) show intact posterior spinal elements at L4 (arrow) and a defect beginning at L5 (dashed arrow). The surface rendering assists in visualizing the 12^th ribs (arrowheads) and identifying spinal levels but is not particularly helpful in visualizing the defect itself.